arm64: Rename reserved values for CTR_EL0.L1Ip

arm64: Rename reserved values for CTR_EL0.L1Ip

We now have *two* values for CTR_EL0.L1Ip that are reserved.
Which makes things a bit awkward. In order to lift the ambiguity,
rename RESERVED (0b01) to RESERVED_AIVIVT, and VPIPT (0b00) to
RESERVED_VPIPT.

This makes it clear which of these meant what, and I'm sure
archeologists will find it useful...

Reviewed-by: Zenghui Yu <yuzenghui@huawei.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20231204143606.1806432-4-maz@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>